1. Field of the Invention
The present invention relates to an apparatus for moving supports for sensors or the like in submarines, which comprises actuating means of the electrical type.
2. Description of Related Art
It is known in the technical sector of submarines that there is a need to raise above the surface of the water, when the submarine is at periscope height, a certain number of sensors of the passive and active type, such as radar and/or radio antennae, optronic heads and the like which are normally housed inside the tower (or sail) of the submarine and fixed to displaceable tubes and which, when required, are displaced vertically by suitable hydraulic raising devices until they are brought outside the free surface of the water situated above the tower.
It is also known that these vertical displacement apparatus must be particularly silent in order to avoid detection by means of acoustic signals, able to withstand the pressure underwater produced at the navigation depth of the submarine, resistant to corrosion by the seawater and able to raise the sensor-support tube, overcoming not only the weight thereof, but also the friction produced by the hydrodynamic thrust of the water, owing to the movement of the submarine, on the guides for sliding of the said tube, which transverse thrust is responsible for most of the overall resistance to displacement in the vertical direction.
For this purpose, apparatus which envisage the use of oil-dynamic actuating systems are known in the art, said systems, however, requiring a hydraulic system comprising among other things a pumping station with consequent constructional complications and an increase in the maintenance requirements in order to protect the purity of the oil from water infiltration.
In addition to this, the hydraulic cylinder actuating system has further drawbacks such as the large weight of the actuator and the associated hydraulic circuit, the need to convert the power from its electrical form available on-board into a hydraulic form with associated devices and loss of efficiency, and the sensitivity of the position transducer to electromagnetic disturbances since they are situated in the vicinity of the displaced sensor which may be a broadcasting antenna.